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> You don't need to be there yourself. lol, dunno if you are aware or not - but the Arecibo telescope catastrophically collapsed on itself. Serviceability is t

> You don't need to be there yourself. lol, dunno if you are aware or not - but the Arecibo telescope catastrophically collapsed on itself. Serviceability is the concern. The maintenance logs are long for scientific instruments, there is no such thing as a 'set it and forget it' telescope.

ncmncm 5y ago
Hubble has been visited I think twice in 3 decades.
- sennight 5y ago
  That is an interesting choice for a counter example, because when I think of Hubble I think of failed gyroscopes. Hubble has required 5 servicing missions and always seems to be at risk of moving from a state of crippled-but-still-useful to flat-out-busted-forever. Look at the program's weekly observation logs, keep an eye on the file size - the interesting ones are smaller than average. Gyros and safemode. If you suddenly feel the urge to blurt out "Bbut funding and politics!", then consider my point proven - a Moon based telescope would be far more vulnerable to such externalities. https://www.stsci.edu/ftp/observing/weekly_timeline/ https://www.stsci.edu/ftp/observing/weekly_timeline/
  - ncmncm 5y ago
    A telescope on the moon will not need any gyroscopes. The first Hubble visit was to fix a manufacturing/testing flaw impossible in a radio telescope. Arecibo's failure would also be impossible, as there is no oxidation and no weather on the moon. The only likely failure mode would be from metal fatigue as a consequence of temperature swings, but they are 100% predictable. Maybe you are not aware of the very large difference between an optical telescope and a radio telescope? Optical telescopes always have many precision moving parts. Radio telescopes often have none at all. Anyway, in ten years, given promised SpaceX Starship progress, a visit will be much cheaper than a single Shuttle visit to ISS. Probably such progress will end up turning on thousands of heat-shield tiles not each needing a diaper change after each flight, as the current design seems to require.

ncmncm 5y ago

Hubble has been visited I think twice in 3 decades.

sennight 5y ago
That is an interesting choice for a counter example, because when I think of Hubble I think of failed gyroscopes. Hubble has required 5 servicing missions and always seems to be at risk of moving from a state of crippled-but-still-useful to flat-out-busted-forever. Look at the program's weekly observation logs, keep an eye on the file size - the interesting ones are smaller than average. Gyros and safemode. If you suddenly feel the urge to blurt out "Bbut funding and politics!", then consider my point proven - a Moon based telescope would be far more vulnerable to such externalities. https://www.stsci.edu/ftp/observing/weekly_timeline/ https://www.stsci.edu/ftp/observing/weekly_timeline/
- ncmncm 5y ago
  A telescope on the moon will not need any gyroscopes. The first Hubble visit was to fix a manufacturing/testing flaw impossible in a radio telescope. Arecibo's failure would also be impossible, as there is no oxidation and no weather on the moon. The only likely failure mode would be from metal fatigue as a consequence of temperature swings, but they are 100% predictable. Maybe you are not aware of the very large difference between an optical telescope and a radio telescope? Optical telescopes always have many precision moving parts. Radio telescopes often have none at all. Anyway, in ten years, given promised SpaceX Starship progress, a visit will be much cheaper than a single Shuttle visit to ISS. Probably such progress will end up turning on thousands of heat-shield tiles not each needing a diaper change after each flight, as the current design seems to require.